Abstract
Among men and women attending the sexually transmitted diseases (STD) clinic the exposure rates to Chlamydia trachomatis serotypes D to K (genital pathogens) were 18 multiplied by 7% and 26 multiplied by 7% respectively. Antibody titres suggesting active disease in these men and women were found in 11 multiplied by 8% and 22 multiplied by 7% respectively. The higest rate of exposure (35%) was among women attending the family planning clinic; of these women 25% had antibody suggesting active disease. Titres of IgG antibody in this study were similar to those found among men and women with chlamydial genital infections in the United Kingdom. The results suggest that the prevalence of chlamydial genital infections in Ibadan, both among STD patients and especially among those individuals not seeking treatment (family planning and antenatal clinic patients), is high.